How does I80 compare with I70 as far as mountain passes and quality of hwy?

I-80 through Wyoming is up-hill, into the wind either direction and generally very boring. Once you hit Park City, UT it's not so bad. Consider taking I-70 and pick a route that gets you up to US-40 which will take you up to I-80 at Park City. I personally like I-70 to Rifle and then through Meeker and Rangely to Dinosaur to pick up US-40.